Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bioreactor boosts chemical fermentation by 50 percent: study

30.03.2004


A device invented at Ohio State University has dramatically boosted the production of a chemical that performs tasks as diverse as scenting perfume and flavoring Swiss cheese.


Shang-Tian Yang



Engineers here have used their patented fibrous-bed bioreactor to genetically alter a bacterium so that it produces 50 percent more of the chemical propionic acid than the organism produces normally. And it did so without the aid of chemical additives employed in industry.

The device also reduced the amount of two unwanted byproducts that normally result from propionic acid fermentation -- cutting one byproduct by more than half, said Shang-Tian Yang, professor of chemical engineering at Ohio State.


The bioreactor grows cells inside a bundle of fibers. Yang and his colleagues have previously shown that they could control the growth and differentiation of cells by changing the packing density of the fibers in the bioreactor.

Monday at the national meeting of the American Chemical Society in Anaheim, Yang and doctoral student Supaporn Suwannakham reported that they were able to produce 72 grams of propionic acid per liter of sugar solution inside the bioreactor. Traditional fermentation typically yields only 50 grams per liter or less, making the new process 44 percent more effective.

More important to Yang is the fact that he and his team were able to coax the bacterium P. acidipropionici to make more acid without adding chemicals to the mix. They simply immobilized the cells on the fibers so the cells could grow and evolve -- or mutate -- in a harsh environment.

“Most labs focus on mixing the right chemical or biological cocktail to grow cells,” he said. “We are the only group that I know of that is working to optimize the cells’ physical environment.”

The bioreactor can grow cells for a variety of applications including fermentation, animal cell culture, tissue engineering, and waste water treatment. Since 1998, Yang and his colleagues have used the device to make large quantities of a protein -- Developmental Endothelial Locus-1 Protein -- for cancer research. A commercial company recently licensed the technology for agricultural applications.

Yang designed the bioreactor as a three-dimensional alternative to the flat petri dishes and trays that scientists traditionally use to culture cells. The fibers anchor living cells in place as they grow and reproduce.

For this latest study, the engineers grew P. acidipropionici in a sugar solution, and gradually adjusted the sugar concentration so the cells would tolerate -- and produce -- higher concentrations of propionic acid. Tests yielded an average of 72 grams of the acid per liter. The bioreactor also produced 52 percent less succinate and 14 percent less acetate -- two chemicals that industry normally has to remove from the fermentation mix before the propionic acid can be used.

When Yang and Suwannakham examined the cells from the bioreactor, they found that the cells had mutated and changed several key enzyme activities. Production of enzymes for propionic acid formation had increased, and the enzyme for succinate production had decreased.

Aside from giving Swiss cheese its characteristic smell and flavor, propionic acid is often used as a preservative and flavor enhancer for a wide variety of cheeses and baked goods.

In the chemical industries, it’s used as an ingredient for dyes, perfumes, pharmaceuticals, herbicides, rubber, and plastic.

With today’s growing emphasis on organic or “all-natural” products, Yang sees a market for propionic acid made without chemical additives in the bioreactor. “A company could conceivably market a product as being made with ‘all-natural’ propionic acid,” he said.



Contact: Shang-Tian Yang, (614) 292-6611; Yang.15@osu.edu
Written by Pam Frost Gorder, (614) 292-9475; Gorder.1@osu.edu

Pam Frost Gorder | Ohio State University
Further information:
http://researchnews.osu.edu/archive/propacid.htm

More articles from Life Sciences:

nachricht Toward a 'smart' patch that automatically delivers insulin when needed
18.01.2017 | American Chemical Society

nachricht 127 at one blow...
18.01.2017 | Stiftung Zoologisches Forschungsmuseum Alexander Koenig, Leibniz-Institut für Biodiversität der Tiere

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>